The Soviet policy in WWII was to concentrate rigidly on one model for each type of weapon, but during the siege of Leningrad the supply of PPSh41s fell very low. A prototype was hurriedly developed in a local factory in a design suitable for the equipment available. Quite naturally, it was simple in the extreme, but proved to be quite effective and was subsequently developed into the PPS43. Unusual for a Soviet weapon, the PPS43 used only the 35 round box magazine.
The Chinese used this model extensively in Korea, as well as a home-made version of the PPSh41, although at first they had far more weapons of other types: Japanese, Chinese Nationalist, US, British, and others. The light weight, both of the basic weapon and the box magazine, together with the foldable stock, were attractive to the Chinese army, which was essentially infantry, operating on Guerilla principles of moving large distances in short times, on foot.